Capacitive multi-touch surfaces can detect the positions of one or more fingers on the surface, but cannot uniquely identify objects placed on the surface. Optical multi-touch tables, which use a camera/projector system or sensor-in-pixel technology, have the ability to identify objects equipped with a visual marker as well as sense multi-touch user input. However, such tables are large, have rigid form-factor limitations (because of the optical arrangement) and a high power consumption.